How to edit stress periods in previously-run NWT models?

[ECR2002]

Hello,

I am new to flopy, and had some questions regarding editing previously-built models.

The model that I am interested in is here (https://www.twdb.texas.gov/groundwater/models/gam/hpas/hpas.asp). It is a pretty large model for part of the Ogallala Aquifer, that was ran for 84 stress periods (years), ending in 2012. I would like to be able to load this model, make some changes to it, and bring it up to date. I am able to load and run the model just fine, but I can't seem to figure out how to add additional stress periods. Is there a function to append additional stress periods to the model?

Thanks!